Introduction of MySQL in the cluster mode
					
This file is mainly depend on the article that is published on the website 
http://dev.mysql.com/tech-resources/articles/mysql-cluster-for-two-servers.html
I strongly recommended you to read this article three times,
and my article will give some additional to setup
on the server when you follow the instruction in the article.

Problems:
	1, can not start the mysql server when you run the command
    "service mysql.server start"
      first to check the config file of /etc/my.cnf
      if not has this file ,please copy the file
      $FULL_PATH_OF_MYSQL_RELEASE/support-files/my-medium.cnf to /etc/my.cnf
              
      If you do so ,can not start the mysql then
      please check the file of `hostname`.err this file is usually
      in the directory of /usr/local/mysql/data/ directory 
              
      at the last line ,you probably see these information 
      1)  can not create $hostname.pid file, if so,
        please check the whole directory access ability of the mysql .
          The method is to use the command
          shell > su mysql
          shell > cd /usr/local/mysql/data 
          shell > touch `hostname`.pid
          Mostly you can not access the directory or make the file
          then chmod or chown of the directory
                  
      2)  Can not open and lock privilege tables : Table 'mysql.host'
          This is because you do not call the scripts/mysql_install_db
          rightly please run the command
          $FULL_PATH_OF_MYSQL_RELEASE/scripts/mysql_install_db  --user=mysql again
                  
                  
Use of cluster
       If you follow the instruction of the file you will call the
       instruction very well but you will be sure of 
       use the engine like this 
       ENGINE=NDBCLUSTER
       
       This will call the database engine of remote backup.
       so you can see the database change on the other node.
       But there is some disconformity on the alter table,
       it is said in the MySQL tutorial in this website
       http://dev.mysql.com/doc/refman/5.0/en/mysql-cluster-limitations.html 
       Maybe this is the shortage of MySQL database compensating
       for speed of clusters.